Add improved CLI interface for removing remote media (#8411)

./bin/tootctl media remove --days 7 --background

Make the old rake task point to it

lib/cli.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+require 'thor'
+require_relative 'mastodon/media_cli'
+
+module Mastodon
+  class CLI < Thor
+    desc 'media SUBCOMMAND ...ARGS', 'manage media files'
+    subcommand 'media', Mastodon::MediaCLI
+  end
+end